The present invention relates to a filter for a device for providing a ready-to-drink nutritional composition such as an infant formula. More particularly, the present invention relates to an exchangeable filter card which is removably insertable into a device in order to improve the hygiene level and ease the maintenance of the device.
Infant formulas have been developed as a substitute for human breast milk in order to provide required nutrients to infants. In general the infant formulas are either based on cow or soy milk and may be provided in different forms such as powder or concentrated liquid form.
Each of the different forms in which infant formulas may be provided has their own advantages. For instance, although the infant formula provided in a powder form has a relative high nutritional quality, the preparation thereof may be regarded as inconvenient and time consuming, since water which has been boiled in advanced and allowed to cool has to be poured into a sterilised drinking vessel containing the powder in order to prepare a liquid infant formula. The same inconvenient preparation process exists for infant formulas in concentrated liquid form.
If prepared and consumed in this manner, powdered infant formulas provide a safe and nutritionally good substitute for mother's milk. However, primarily due to the inconvenient preparation, many parents or caregivers do not prepare the formulas properly and hence expose the infant to risks of infection or other risks. For instance, if water is not properly sterilized prior to use or if the final preparation is prepared too long in advance, there can be a risk of transmitting pathogens to the infant. Usually, water sources in developed countries are safe but this may not be the case everywhere.
In further development, infant formulas in ready-to-feed single serve portions have been introduced which overcome the inconvenience of the preparation of the infant formula. However, these ready-to-feed products are more costly than infant formulas stored in bulk and they often suffer the disadvantage that once the portion is opened, it has to be consumed immediately to avoid the risk of contamination with bacteria. Moreover, even the single serve portion infant formulas are reconstituted with water. Hence, there is a risk that the water may not necessarily be properly sanitized and that the single serve baby bottles are prepared in advance in bulk and stored.
The immune defences of infants and young children are generally not fully developed and, as a result, these populations are particularly vulnerable to both bacterial and viral infections. For example, they may be prone to infections in circumstances where the immune system of a healthy adult would resist infection or they may suffer more serious consequences as a result of infection than would a healthy adult. Similar difficulties may arise in populations where the immune system is compromised such as the elderly. The consequence of this is that devices that prepare nutritional compositions which are perfectly safe for healthy adults may not be able to produce products which meet the increased safety standards required for products to be consumed by subjects having immature or compromised immune systems.
Therefore, a method or an apparatus is sought-after which enables a provision of nutritional composition for instance an infant formula in a convenient and safe manner.
WO2006/077259 discloses a method for preparing a single serving of a nutritional composition comprising introducing liquid such as water into a cartridge containing a unit dose of the composition in concentrated form. Thereby, the water is treated prior to the introduction into the cartridge in order to remove pathogens from the water. This treatment may be for instance a pre-heating, a filtering or an irradiation of the water with ultra-violet light.
A device which teaches the principle of treating water by means of a filter used for the preparation of nutritional compositions in a dispenser from cartridges is disclosed in co-pending European patent application No. 06117801.8 filed 25 Jul. 2006 entitled “Dispenser for preparing a nutritional composition”. Accordingly, a convenient solution for treating the water can be provided in order to ensure that the water is free of pathogens. However, the filter in the disclosed device is incorporated in the water discharge means.
In order to ensure a high standard of safety with regard to the removal of any pathogens which may be contained in a liquid used for the preparation of a nutritional composition, the provided filter of such a device may have to be changed repeatedly. Therefore, an improved filter system is sought-after which enables exchangeability and/or maintenance of the filter to provide the necessary level of hygiene and food safety.
US20070199888 relates to a water filter for a coffee machine that has tabs to be attached to the brew basket of a machine. However, this water filter is simply slidably engaged below a brewing basket which receives water at atmospheric pressure. The filter is said to have a thickness of several millimeters. However, this filter is not intended to remove pathogens to treat water.
WO01/50875A1 relates to a drip coffee brewer comprising a liquid reservoir connected to a heater and a liquid outlet positioned above a supporting device holding a filter assembly. The filter assembly is designed to remove pathogens. The filter is configured with a reservoir to be able to receive dripping water which accumulates against the filter. Such system is so designed to slowly filter water at atmospheric pressure by a principle of percolation. Furthermore, the filter assembly requires a complex filtering structure including an adsorbent supporting web substrate having a surface fused to a mixture of adsorbent particles and binder particles.
The present invention seeks to address the above described problems. The invention also aims at other objects and particularly the solution of other problems as will appear in the rest of the present description.
In particular, the invention aims at providing a solution for supplying water, free of undesired micro-organisms in a device for preparing a nutritional composition, at a certain pressure (above atmospheric) and flow rate for an effective interaction with the ingredients.